You don't need any program to do it. I've just received a new ipod nano and wanted all the stuff on my old ipod transferred to it. I followed these rules:
Connect the iPod to your PC. If iTunes starts syncing (ie erasing) your music automatically, hit the X in the upper right hand corner of iTunes display, to the left of the search box, to stop it.
In Control Panel, Portable Media Devices, double-click your iPod.
In the Tools menu -> Options, in the View Tab, check "Show hidden files and folders."
Navigate to the Music folder. On my 2nd gen 'pod, the full path is
Portable Media Devices\IPOD NAME\iPod_Control\Music
Select all the music folders, and drag and drop them into a folder on your hard drive, or directly into iTunes.
I found that the best thing to do was to drag the files to the itunes music folder and set itunes to organize the files which puts them back into the correct order.
It took a while to do just ove 6MB of music but it got there in the end. It was also better to do three or four folders at a time rather than all fifty at once.
Good luck!